INTO A SPACE › into an area or space from the outside of it: He rushed in halfway through the meeting. Annie opened the car door and threw her luggage in.
AT A PLACE › at the place where a person usually lives or works: I phoned, but she wasn't in. Could you ask him to ring me when he gets in?
TRAIN/PLANE › If a train, plane, etc is in, it has arrived at the place it was going to: My train gets in at 17.54.
SENT › given or sent to someone official in order to be read: Applications must be in by 28th February.
TOWARDS LAND › used when the sea or a ship moves close to land: Let's go - the tide is coming in.
be in for sth informal › If someone is in for a surprise, treat, shock, etc, it will happen to them soon: If he thinks looking after a baby is easy, he's in for a shock.
be in on sth informal › If you are in on something, you know about it or are involved in it: Were you in on the surprise? Please let me in on (= tell me) the secret.
SPORT UK › In cricket and similar sports, if a person or team is in, they are taking a turn to play.
be in for it (also UK be for it) › to be in trouble